Its nearest point to the sun is 29 million miles and the maximum distance is 43 million miles away. Mercury's surface contains rough, porous, dark-colored rock. Spectroscopic studies say that only a very thin atmosphere, containing sodium and potassium, exists on Mercury. Mercury has been hit by so many comets and asteroids that its surface is full of craters. It takes 88 Earth days for Mercury to orbit around the sun. It is the second smallest planet. It takes Mercury 59 Earth Days to rotate around its axis. Mercury is the only known planet on which the day is longer than the year. Mercury resembles the Earth's moon. This planet has no moon. Mercury's day equals 3 Earth months. Mercury's gravity is about one-third of the Earth's gravity. Mercury's diameter is 3,025 miles. Mercury consists of virtually no atmosphere. Mercury has a weak magnetic field and a trace of atmosphere one-trillionth the density of the Mercury's iron core is about the size of the Earth's moon.
Venus.
It is the second planet in distance from the sun. Other than the sun and moon, Venus is the brightest object in the sky. This planet is called the morning star and the evening star. Long ago, the morning star was called Phosphorus or Lucifer and the evening star was called Hesperus. Venus is named after the goddess of love in ancient Rome. Its rocky surface traps the suns heat, making Venus the hottest planet. The approximent temperature is about 900 degrees Fahrenheit. The atmosphere consist of 97% carbon dioxide. It is the only planet to spin backwards, from east to west, very slowly. Venus is Earth's sister planet. Venus is 5 % smaller and 19 % less massive than Earth, and its density is almost the same as Earth. The atmospheric pressure of Venus is 97 times that of Earth. Venus' upper clouds contain sulfuric acid. No magnetic field is found on Venus. Venus circles the Sun every 224.7 Earth days. One Venus day would equal 243 Earth days.